天长地久有多久地久天长有多长
        
            [tiān zhăng dì jiŭ yŏu duō jiŭ dì jiŭ tiān zhăng yŏu duō zhăng]
        
        
            A play on words reflecting a yearning for eternal love or friendship. It is questioning how long is 'eternal'. It emphasizes the desire for love and relationships that last through time.